REST: is it possible to skip some attributes from entity in request

Is it possible to skip some atrributes in a POST request object?

So if I have for example the entity Customer with attributes Name and LastName they json generated will look like:

{"Name":"Erik", "LastName":"Nobel" }

The webservice I have to use does not allow me to send empty attributes. So if in this example the Name attribute would be empty or empty string the json should look like:

{"LastName":"Nobel" }